The present invention relates generally to turbine shroud assemblies and more particularly to a discourager for use in a turbine shroud assembly.
Shrouds are used in turbines and engines to act as an interface between rotating blades and a casing structure. The shroud provides tight tip clearance to the blades, and provides a mounting for the nozzles. Typically, such shrouds are made of a metal material. However, industrial gas turbine and aircraft engine shrouds operate in a high temperature environment and therefore require cooling to obtain a useful design life cycle. An alternative to using a metal shroud with cooling air is to use a ceramic matrix composite (CMC) material for the shroud, thus eliminating the required cooling of the shroud due to the CMC's superior temperature capability over metal. The CMC shroud typically includes seals to prevent the high heat at the end of the shroud nearest the gas/steam path from reaching the end nearest the metal outer casing. Typically, the seal must be cooled in order to effectively seal the shroud end gaps to maintain design life of the seal.